Wireless devices are playing an increasingly significant role as a communication tools throughout the world. Examples of wireless communication devices include portable radios, cellular or wireless telephones, pagers, electronic messaging devices, and the like. As the cost of ownership of wireless communication devices has become more affordable, such devices have become a necessity for many people.
Today, there are over 123 million wireless mobile phone subscribers in the United States alone. Because of the increased use and dependence of wireless communications throughout the world, being able to communicate to others irrespective of one's location is of critical importance. Two factors may affect a subscriber's ability to utilize wireless communication network. First, the coverage of the network, which is a function of the number of base stations and second, the ability of the subscriber's wireless communication device to receive the signal.
One drawback of existing wireless communication devices is an inability to effectively receive an incoming voice or data signal. To achieve reception, the incoming electromagnetic signal is picked up by an antenna, which is responsible for transmitting and receiving the modulated carrier signal that contains the desired signal (voice or data) information. The wireless communication device's ability to capture, demodulate, and decode the received signal will depend on a number of factors, such as the signal strength and nearby signal obstructions.
For example, existing wireless communication devices may have difficulty receiving a signal in the presence of tall structures, such as buildings found in metropolitan environments. In such environments, the original signal is often cluttered with replicas of the original signal that are weaker in amplitude. This often causes problems in reception as it becomes difficult for the discriminator of the mobile communications device to detect the original signal.
Furthermore, there are changing environmental factors such as precipitation and terrain that could affect the signal strength or create signal reflections, and hence affect the wireless communication device's ability to receive the signal. In addition, dead spots encountered in mountainous or wooded areas can block or weaken signals and are a serious drawback to wireless communication.
The drawbacks mentioned above are factors which contribute to a reduction of the signal to noise ratio (SNR) of a signal provided to a transceiver of the wireless communication device. This correlates to an increase in a symbol or bit error rate of a demodulated baseband digital signal. When receiving voice information, these above-mentioned drawbacks may result in a decrease in perceived speech quality. In the case of data, the net result may be significant packet loss due to bit errors. As a result, there exists a need for a method and apparatus to more effectively capture and process the signal at the wireless mobile communication device.